Drum type washing machine with laundry drying function

ABSTRACT

Drum type washing machine having a laundry drying function including a tub for receiving hot air through a front, and discharging the hot air through a rear, a drum rotatably mounted in the tub, a drying duct connected to a hot air inlet hole in the tub for guiding the hot air to a hot air inlet side of the tub, a heater for producing the hot air, and a fan for forced circulation of the hot air to a drum side, and a condensing duct for removing moisture from the hot air from the hot air outlet hole in a lower portion of the rear of the tub, thereby improving a drying efficiency and a drying performance.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Application No.P2004-0026738 filed on Apr. 19, 2004, which is hereby incorporated byreference as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to drum type washing machines, and moreparticularly, to a drum type washing machine with a laundry dryingfunction, in which a new flow passage structure is employed forimproving a drying efficiency, and a drying performance.

2. Discussion of the Related Art

In general, the drum type washing machine is an apparatus for washinglaundry by rotating a drum with a driving force of a motor in a statedetergent, washing water, and the laundry are introduced into the drum.The drum type washing machine has advantages in that damage to thelaundry is small, entangling of the laundry is small, and a washingeffect of pounding and rubbing can be made.

A related art drum type washing machine will be described in detail,with reference to FIG. 1. FIG. 1 illustrates a side section of a relatedart drum type washing machine, schematically.

Referring to FIG. 1, the related art drum type washing machine isprovided with a cabinet 1 having a front opening for introduction oflaundry, a door 2 mounted at the opening of the cabinet 1 foropening/closing the opening, a metal tub 3 in the cabinet 1 for holdingwashing water, a drum 4 rotatably mounted in the tub 3, and a motor unit5 mounted on the tub 3, for providing driving force to the drum 4.

The door 2 has a glass 2 a projected toward an opening of the tub 3.

There are hanging springs 6 between an inside of a top of the cabinet 1and a top of an outside circumference of the tub 2, and, though notshown, there are dampers (not shown) between an inside of a bottom ofthe cabinet 1 and an underside of the outside circumference of the tub2, for damping vibration of the tub 2 occurred during operation of thedrum washing machine.

As the motor unit 5, an indirect coupling type is used mostly, in whichthe driving force is transmitted from a motor 5 a to a washing shaft 5 cvia a belt 5 b for rotating the drum 4.

In the meantime, there is a drying duct 7 in an upper portion of aninside of the cabinet 1. The drying duct 7 has a heater 7 b and a fan 7a for producing hot air and forced blowing of the hot air.

One end of the drying duct 7 is connected to a gasket 8 connectedbetween a circumference of the front opening of the tub 3, and acircumference of the door at the front of the cabinet 1.

That is, the gasket 8 is mounted along a front inside circumference ofthe tub 3, and has a bellows shape for absorbing vibration of the tub 3.According to this, leakage of hot air through a connection of the dryingduct 7 and the tub 3 is prevented.

The tub 3 has a condensing duct 9 connected to the drying duct 7. Thecondensing duct 9 has one end connected to an outside of the tub 3, andthe other end connected to the drying duct 7. The condensing duct 9 hasa water supply device 9 a mounted thereon for supplying cooling water tocondense, and remove moisture from air.

The drum type washing machine performs a washing cycle, a rinsing cycle,a spinning cycle, and a drying cycle.

The drying cycle of the drum type washing machine will be described.

Upon starting the drying cycle of the drum type washing machine, poweris applied to the heater 7 b on the drying duct 7. As the fan 7 a andthe heater 7 b are put into operation, the fan 7 a blows hot air.

The hot air is guided by the drying duct 7, hits a sloped portion of thedoor glass 2 a, and, therefrom, is introduced into an inside of the drum4.

Then, the hot air heats laundry and vaporizes moisture from the laundry.In the instance, the drum 4 rotates slowly, to turn the laundry upsidedown, so that the laundry is exposed to the hot air uniformly, to helpvaporization of the moisture.

The moisture vaporized thus is discharged through the condensing duct 9carried by the air. In this instance, by spraying water from the watersupply device 9 a of the condensing duct 9, the moisture is removed fromthe air. The air having the moisture removed therefrom thus isintroduced into the drying duct 7 again, and turned into hot air by theheater 7 b and the fan 7 a, and introduced into the drum 4 again, forperforming drying of the laundry.

By repeating the foregoing process, the laundry is dried.

However, the related art drum type washing machine has problems in manyaspects, such as the related art drum type washing machine haslimitations in drying efficiency and drying performance because therelated art drum type washing machine has a circulating structure inwhich the hot air is supplied to the inside of the drum through theconnection portion of the drying duct at one side of an upper portion ofthe gasket, and discharged through a side of a front of the tub again.

First, because the air is discharged through the side of the front ofthe tub in a state the air supplied to the inside of the drum can notpenetrate deep into the inside of the drum yet, drying of the laundry atthe deep inside of the drum has not been adequate. Therefore, therelated art flow passage structure has disadvantages of dropping thedrying efficiency, and the drying performance.

Second, the gasket is liable to wear and tear because the gasket, whichmoves according to vibration of the tub, is connected to the drying ductwhich is fixedly secured, to require an expensive gasket 8 which has arelatively small thermal deformation, to increase a production cost.

The vertical downward discharge of the hot air from the drying gasket 7through the gasket causes the problem that the hot air fails thepenetration deep into the inside of the drum, because the verticaldownward direction is away from a direction of the shaft of the drum,and the hot air hits the door glass to have a resistance from the doorglass. In order to overcome this problem, a fan with a large capacity isrequired.

Moreover, as described before, because the hot air is introduced intothe drum 4 through the drying duct 7, and the gasket 8, and deflected atthe sloped portion of the door glass 2 a, the door 2 is heatedunnecessarily.

In the meantime, the connection of the drying duct 7 to an outsidecircumference of upper side of the gasket 8, making the gasket 8asymmetric between an upper side and a lower side of the gasket 8,causes the gasket to fail in balanced holding of a front of the tub 3.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a drum type washingmachine with a laundry drying function that substantially obviates oneor more problems due to limitations and disadvantages of the relatedart.

An object of the present invention is to provide a drum type washingmachine with a laundry drying function, which has a new improved flowpassage structure for improving a drying efficiency and a dryingperformance.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, adrum type washing machine having a laundry drying function includes atub for receiving hot air through a front, and discharging the hot airthrough a rear, a drum rotatably mounted in the tub, a drying ductconnected to a hot air inlet hole in the tub for guiding the hot air toa hot air inlet side of the tub, a heater for producing the hot air, anda fan for forced circulation of the hot air to a drum side, and acondensing duct for removing moisture from the hot air from the hot airoutlet hole in a lower portion of the rear of the tub.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings;

FIG. 1 illustrates a side section of a related art drum type washingmachine, schematically;

FIG. 2 illustrates a side section of a drum type washing machine inaccordance with a preferred embodiment of the present invention;

FIG. 3 illustrates an exploded perspective view of key parts of FIG. 2;and

FIGS. 4A and 4B illustrate front views showing different embodiments ofarrangements of hot air holes in a front of the drum in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

FIG. 2 illustrates a side section of a drum type washing machine inaccordance with a preferred embodiment of the present invention, FIG. 3illustrates an exploded perspective view of key parts of FIG. 2, andFIGS. 4A and 4B illustrate front views showing different embodiments ofarrangements of hot air holes in a front of the drum in FIG. 2.

Referring to FIGS. 2 and 3, the drum type washing machine in accordancewith a preferred embodiment of the present invention includes a tub 20in a cabinet 10 for holding washing water, having hot air inlet hole 20a in an upper portion of a front, and hot air outlet hole 20 b in alower portion of a rear, a drum 30 rotatably mounted in the tub 20,having a plurality of hot air pass through holes 30 a of a predeterminedarray in a front, a drying duct 40 fixedly secured to an outsidecircumference of an upper portion of the tub 20, having a heater 41 anda fan 42 mounted therein for producing hot air, and one end connected tothe hot air inlet holes in the tub 20 for supplying the hot air from thedrying duct 40 to the drum 30, and a condensing duct 50 mounted in rearof the tub 20 such that one end thereof is connected to the hot airoutlet hole 20 b at the lower portion of the rear of the tub 20, and theother end thereof is connected to the drying duct 40, for removingmoisture from the air discharged from the tub 20.

It is preferable that the tub 20 is a plastic injection molding, and thedrum 30 is formed of stainless steel.

The hot air pass through holes 30 a in the drum 30 are arranged in aradial direction, on the whole (see 4A, and 4B).

In more detail, referring to FIG. 4A, the hot air pass through holes 30a in the front of the drum 30 are arranged in concentric circles in acircumferential direction as the holes go from an inner side to an outerside of the radial direction, with the hot air pass through holes 30 ain each of the concentric circles are aligned in a line in the radialdirection.

That is, referring to FIG. 4A, the hot air pass through holes 30 a ineach of the concentric circles are arranged such that the hot air passthrough holes 30 a in each of the concentric circles are in the sameline drawn outward from a center of the drum 30 in the radial direction.

Referring to FIG. 4B, the hot air pass through holes 30 a in the frontof the drum 30 are arranged to form concentric circles in acircumferential direction as the hot air pass through holes 30 a go froman inner side to an outer side in the radial direction, not in a radialline drawn outward from the center of the drum in the radial direction,but in a zigzag form along the radial line.

In the meantime, the drying duct 40 is fixedly secured to an outside ofa top side of the tub 20 with fastening members, such as screws, with aheat shielding plate 43 between the tub 20 and the drying duct 40 forshielding transmission of heat from the drying duct 40 to the tub 20.

That is, the heat shielding plate 43 is fastened to the outside of thetub 20, and the drying duct 40 is fastened to the heat shielding plate43 with fastening members, such as screws, in a state the heat shieldingplate is secured to the tub.

In the meantime, even though it is preferable that the drum 30 isrotated by direct coupling type outer rotor type BLDC motor including ashaft 61 passed through the tub 20 and coupled to the drum 30, a rotor62 coupled to a rear end portion of the shaft 61, and a stator 63secured to a rear wall of the tub 20 so as to be positioned on an innerside of the rotor 62, the rotating system of the drum 30 is not limitedto above.

There may be heat dissipation means, such as heat dissipation fins 44,on an upper surface of the drying duct 40 for increasing a heatdissipation area to prevent the upper surface of the drying duct fromoverheating.

The operation of the drum type washing machine having a laundry dryingfunction of the present invention will be described.

The tub 20 has the hot air inlet hole 20 a in the upper portion of thefront of the tub 20, and the hot air outlet hole 20 b in the lowerportion of the rear of the tub 20, making the hot air to flow in adiagonal direction in the tub 30, enabling the hot air to reach deepinto an inside of the drum uniformly throughout the drum to dry thelaundry uniformly.

The hot air pass through holes 30 a in the front surface of the drum 30,opposite to the hot air inlet hole 20 a in the upper portion of thefront of the tub 20, are arranged in concentric circles, in the sameline drawn outward from a center of the drum 30 in the radial directionas shown in FIG. 4A, or in a zigzag form along the radial direction asshown in FIG. 4B.

That is, the hot air pass through holes in the front of the drum 30 arearranged such that a flow passage cross sectional area is the maximumwhile strength of the front of the drum 30 is not impaired.

The effective arrangement of the hot air pass through holes 30 athroughout the entire front surface of the drum 30, such that the hotair inlet hole 20 a and the hot air pass through holes 30 a are incommunication even if the drum 30 rotates, enables supply of the hot airto an inside of the drum 30 smoothly through the hot air pass throughholes 30 a in the front of the drum 30.

In the meantime, the heat shielding plate 43 under the drying duct 40shields transmission of heat from the drying duct 40 to the tub 20.

Along with this, the drying duct 40 fixed to the outside surface of thetub with the heat shielding plate therebetween permits to dispense withthe gasket at a connection portion of the drying duct 40 and the tub 20for absorbing vibration. This is because the drying duct 40 fixed to thetub 20 moves together with the tub 20 when the tub 20 vibrates orshakes.

Of course, it is apparent that a person in this field of art knows thata sealing member may be mounted at the connection portion of the dryingduct 40 and the tub 20 for preventing heat from leaking from the dryingduct 40.

In the meantime, as the condensing duct 50 is secured to the rear of thetub 20 directly too, no gasket is required at a connection portion ofthe condensing duct 50 and the tub 20 for absorbing the vibration.

A drying process of the drum type washing machine having a laundrydrying function will be described.

Upon starting the drying cycle of the drum type washing machine, poweris applied both to the heater 41 in the drying duct 40 and the fan 42,to produce hot air.

The hot air produced thus in the drying duct 40 is introduced into thedrum 30 through the hot air inlet hole 20 a in the front of the tub 20and the hot air pass through holes 30 a in the front of the drum 30.

In this instance, because the hot air pass through holes 30 a arearranged throughout the front surface of the drum so as to maximize theflow passage sectional area while strength of the front of the drum 30is not impaired, and to position the hot air pass through holes 30 aopposite to the hot air inlet hole 20 a even if the drum 30 rotates, thehot air introduced into the inside of the tub 20 through the hot airinlet hole 20 a can be introduced into an inside of the drum 30 directlywithout going around through other path.

Then, the hot air introduced into the drum 30 proceeds toward the hotair outlet hole 20 b in the tub in a diagonal direction, and absorbsmoisture from the laundry, thereby drying the laundry.

In this instance, since the drum rotates slowly to turn the laundryupside down, to expose the laundry to the hot air uniformly, the laundrydrying efficiency is improved.

By rotating the drum 30 slowly, to turn the laundry upside down, and, inthis state, raising the rotating speed of the drum 30 to a level atwhich the laundry does not separate from an inside surface of the drum30, a time period of contact between the hot air introduced into theinside of the drum 30 and the laundry can be increased, adequately.

In the meantime, the hot air, finishing the drying, is discharged to thecondensing duct 50 without temperature drop in a state the hot aircontains the moisture, wherein, as the condensing duct 50 is connectedto the lower portion of the rear of the tub 20 which is diagonal to theupper portion of the drum 30 into which the hot air is introduced, theair can be discharged out of the drum 30 more smoothly through thecondensing duct 50.

That is, because, while the air at the hot air inlet hole in the frontof the tub 20 is light and warm, the air at the hot air outlet hole 20 bin the rear of the tub 20 is relatively heavy and cold, a flow passagestructure of the present invention, in which the hot air inlet hole 20 ais formed in the upper portion of the front of the tub 20 and the hotair outlet hole 20 b is formed in a lower portion of the rear of the tub20, meets to a natural air circulating principle.

Different from the related art, since the hot air is discharged in astate the hot air passes through the drum 30 completely, enabling thehot air to reach to the laundry at a deep place of the drum, the drumtype washing machine of the present invention can improve the dryingeffect.

Moreover, the supply of cold water to the condensing duct 50 from thewater supply device 51 for the moisture laden air introduced into thecondensing duct 50 from the hot air outlet hole 20 b enables removal ofthe moisture from the moisture laden air in the condensing duct 50 owingto a condensing action of the cold water.

The air dried at the condensing duct 50 is introduced into the dryingduct 40 by the fan 42 in the drying duct 40, heated with the heater 41in the drying duct 40, and introduced into the drum 30 by the fan 42,again.

By repeating above process, the laundry is dried.

In the meantime, different from the foregoing embodiment, the dryingduct 40 and/or the condensing duct 50 may be fixedly secured to thecabinet, while the drying duct 40 and/or the condensing duct 50 isconnected to the tub 20.

That is, though not shown, in this case, most of configuration isidentical to the foregoing embodiment except that the drying duct 40and/or the condensing duct 50 is secured to the cabinet 10.

For an example, if the drying duct 40 is secured to the cabinet 10,there is a flexible gasket (not shown) at a connection portion of thedrying duct 40 and the hot air inlet hole 20 a in the tub 20, forpreventing the connection portion suffering from damage or breakage ofthe connection due to vibration at the tub 20.

Of course, the configuration of the gasket on the drying duct 40 side isalso applicable a case of the condensing duct 50 and the hot air outlethole 20 b in the tub 20, if the condensing duct 50 is secured to thecabinet 10.

In the meantime, though not shown, a plurality of hot air inlet holes 20a may be formed in the front of the tub 20, and a plurality of hot airoutlet holes 20 b may be formed in the rear of the tub 20, and, incorrespondence to this change, the drying duct 40 is branched into aplurality of branches at an outlet side, for connection to the pluralityof hot air inlet holes 20 a in the tub, and the condensing duct 50 isbranched into a plurality of branches at an inlet side, for connectionto the plurality of hot air outlet holes 20 b in the tub, for increasinga circulating rate of the hot air.

In the meantime, referring to FIG. 4B, the hot air pass through holes 30a in the front of the drum 130 may be arranged to form concentriccircles in a circumferential direction as the hot air pass through holes30 a go from an inner side to an outer side in the radial direction, ina zigzag form along the radial line, in other words, in a continuousarrangement of honeycomb type of hot air pass through holes 130 a asshown in “A” part in FIG. 4B.

As has been described, the drum type washing machine of the presentinvention having the drying system with a new flow passage structure hasthe following advantages.

First, the new drying system permits deep penetration of the air into aninside of the drum to dry all the laundry uniformly, to improve a dryingefficiency, and a drying performance.

That is, the hot air, produced at the drying duct, is introduced into anupper portion of the drum, flows in a diagonal direction, and isdischarged through a lower portion of a rear of the drum. According tothis, the hot air penetrates deep into an inside of the drum, to improvea drying efficiency, and a drying performance.

Second, different from the related art drum type washing machine havinga laundry drying function, the connection of the drying duct to the tubprevents the gasket from wear and tear.

The symmetric structure of the gasket in an upper side and a lower sideenabled by the connection of the drying duct to the tub permits thegasket to absorb vibration of the tub, uniformly.

Next, different from the related art, as the hot air is introduced intothe drum through the tub without passing through the gasket, theunnecessary heating of the door is prevented.

Fifth, the securing of the drying duct and the condensing duct to thetub permits to dispense with a separate gasket at the connection portionlike the related art, and shortens an air flow passage of the ducts.

Sixth, the drying duct serves as a counterweight, to improve a balanceof the tub.

Seventh, the hot air pass through holes are effectively arranged in thefront of the drum taking strength of the drum, and a flow rate of thehot air introduced into the drum from the drying duct into account.Therefore, the flow rate of the hot air introduced into the drum can bemaximized while the strength of the drum is maintained.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A drum type washing machine having a laundry drying functioncomprising: a tub for receiving hot air through a front, and dischargingthe hot air through a rear; a drum rotatably mounted in the tub; adrying duct connected to a hot air inlet hole in the tub for guiding thehot air to a hot air inlet side of the tub; a heater for producing thehot air, and a fan for forced circulation of the hot air to a drum side;and a condensing duct for removing moisture from the hot air from thehot air outlet hole in a lower portion of the rear of the tub.
 2. Thedrum type washing machine as claimed in claim 1, wherein the hot airinlet hole is formed in an upper portion of a front of the tub, and thehot air outlet hole is formed in the lower portion of the rear of thetub.
 3. The drum type washing machine as claimed in claim 2, wherein thedrum includes hot air pass through holes in a front of the drum forintroduction of the hot air passed through the hot air inlet hole intoan inside of the drum.
 4. The drum type washing machine as claimed inclaim 1, wherein the tub is a plastic injection molding.
 5. The drumtype washing machine as claimed in claim 1, wherein the drying duct isfixedly secured to an outside of the tub.
 6. The drum type washingmachine as claimed in claim 1, wherein the drying duct is fixedlysecured to the cabinet.
 7. The drum type washing machine as claimed inclaim 6, further comprising a flexible gasket between the drying ductand the hot air inlet hole in the tub.
 8. The drum type washing machineas claimed in claim 1, wherein the heater and/or the fan are mounted inthe drying duct.
 9. The drum type washing machine as claimed in claim 1,further comprising heat dissipation fins on an upper surface of thedrying duct for preventing the upper surface from overheating.
 10. Thedrum type washing machine as claimed in claim 1, wherein there are aplurality of hot air pass through holes in the front of the drumarranged in a radial shape.
 11. The drum type washing machine as claimedin claim 3, wherein the hot air pass through holes in the front of thedrum are arranged in concentric circles in a circumferential direction,and in a line in a radial direction.
 12. The drum type washing machineas claimed in claim 3, wherein the hot air pass through holes in thefront of the drum are arranged in concentric circles in acircumferential direction, and in a zigzag shape in a radial direction.13. A drum type washing machine having a laundry drying functioncomprising: a substantially cylindrical tub having a hot air inlet holein an upper portion of a front, and a hot air outlet hole in a lowerportion of a rear; a drum rotatably mounted in the tub, the drum havinghot air pass through holes in a front thereof for introduction of thehot air passed through the hot air inlet hole in the tub into an insideof the drum; a drying duct connected to a hot air inlet hole in the tubfor guiding the hot air to a hot air inlet side of the tub; a heater forproducing the hot air, and a fan for forced circulation of the hot airto a drum side; and a condensing duct for removing moisture from the hotair from the hot air outlet hole in a lower portion of the rear of thetub.
 14. The drum type washing machine as claimed in claim 13, whereinthe tub is a plastic injection molding.
 15. The drum type washingmachine as claimed in claim 13, wherein the drum is formed of stainlesssteel.
 16. The drum type washing machine as claimed in claim 13, whereinthe drying duct is fixedly secured to an outside of the tub.
 17. Thedrum type washing machine as claimed in claim 13, wherein the dryingduct is fixedly secured to the cabinet.
 18. The drum type washingmachine as claimed in claim 17, further comprising a flexible gasketbetween the drying duct and the hot air inlet in the tub.
 19. The drumtype washing machine as claimed in claim 13, wherein the heater and/orthe fan are mounted in the drying duct.
 20. The drum type washingmachine as claimed in claim 13, wherein the hot air pass through holesin the front of the drum are arranged in a radial shape.
 21. The drumtype washing machine as claimed in claim 20, wherein the hot air passthrough holes in the front of the drum are arranged in concentriccircles in a circumferential direction, and in a line in a radialdirection.
 22. The drum type washing machine as claimed in claim 20,wherein the hot air pass through holes in the front of the drum arearranged in concentric circles in a circumferential direction, and in azigzag shape in a radial direction.
 23. The drum type washing machine asclaimed in claim 13, wherein the tub includes a plurality of hot airinlet holes and a plurality of hot air outlet holes, the drying ductconnected to the hot air inlet holes in the tub includes a plurality ofbranches at an outlet side thereof, and the condensing duct connected tothe hot air outlet holes in the tub includes a plurality of branches atan inlet side thereof, so that the branched outlet side of the dryingduct and branched inlet side of the condensing duct are connected to thehot air inlet holes in the tub and the hot air outlet holes in the tub,respectively.
 24. A drum type washing machine having a laundry dryingfunction comprising: a substantially cylindrical tub having a hot airinlet hole in an upper portion of a front, and a hot air outlet hole ina lower portion of a rear; a drum rotatably mounted in the tub, the drumhaving hot air pass through holes in a front thereof for introduction ofthe hot air passed through the hot air inlet hole in the tub into aninside of the drum; a BLDC motor mounted in rear of the tub, the BLDCmotor being directly coupled to the drum; a drying duct connected to ahot air inlet hole in the tub for guiding the hot air to a hot air inletside of the tub; a heater for producing the hot air, and a fan forforced circulation of the hot air to a drum side; and a condensing ductfor removing moisture from the hot air from the hot air outlet hole in alower portion of the rear of the tub.